21023401433 has 4 divisors (see below), whose sum is σ = 21748346340. Its totient is φ = 20298456528.

The previous prime is 21023401429. The next prime is 21023401439. The reversal of 21023401433 is 33410432012.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 4116120649 + 16907280784 = 64157^2 + 130028^2 .

It is a cyclic number.

It is not a de Polignac number, because 21023401433 - 2² = 21023401429 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21023401399 and 21023401408.

It is not an unprimeable number, because it can be changed into a prime (21023401439) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 362472410 + ... + 362472467.

It is an arithmetic number, because the mean of its divisors is an integer number (5437086585).

Almost surely, 2^21023401433 is an apocalyptic number.

It is an amenable number.

21023401433 is a deficient number, since it is larger than the sum of its proper divisors (724944907).

21023401433 is an equidigital number, since it uses as much as digits as its factorization.

21023401433 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 724944906.

The product of its (nonzero) digits is 1728, while the sum is 23.

Adding to 21023401433 its reverse (33410432012), we get a palindrome (54433833445).

The spelling of 21023401433 in words is "twenty-one billion, twenty-three million, four hundred one thousand, four hundred thirty-three".